Integration of System Design and Standard Development in Digital Communication Education Xiaohua(Edward) Li State University of New York at Binghamton
Integration of System Design and Standard Development in Digital Communication Education
Xiaohua(Edward) Li
State University of New York at Binghamton
Contents
Introduction SAM project in digital communications Technical standard of SAM Conclusions
Introduction
Digital communications education should teach theory with a systematic view use MATLAB projects to strengthen the
systematic view develop practical system design experience
Traditional ways of teaching may not perform well enough
Introduction
Our approach: joint theory, system design and technical standard drafting
Objectives: Integrate theory with hands-on experience Cost effective: computers only Convenient: Matlab programming only Competitive: drafting standards
Design of the SAM Project
SAM: soft acoustic modem a modem with PC and MATLAB
Overview: Phase 1: baseband transmission Phase 2: passband transmission (wireline) Phase 3: passband with coding (wireless) Modem standard discussion and draft
Work of students demonstration, presentation, standard draft
The SAM Project (1)
Phase I. Baseband system design Theory: data packet, pulse shaping, synchronizations Hardware: one PC Software: MATLAB
The SAM Project (2)
Phase II. Passband wired transmission Theory: modulation/demodulation, synchronization Hardware: one or two PC Software: MATLAB
The SAM Project (3)
Phase III. Wireless modem Theory: wireless, SNR, channel coding/decoding
Hardware: two PCs
Encoder S1
S2
reg 0 reg 1 reg 2
XOR00
10
01
S1,2
S3,4..
.
...
.
...
S1,2
S3,4
S1,2
S3,4
S1,2
S3,4
S1,2
S3,4
S1,2
S3,4
S1,2
S3,4
.
.
S1,2
S3,4
S1,2
S3,4
00
10
1000
0111
11
The SAM (4). Software: MATLAB
The SAM Project (5)
Typical transmitter and receiver block diagrams
Simulation results of one student group
Start Transmitter Generate random
message
Format message with Barker and
Training SequenceConvolutional encode
messageDifferentially
encode entire signal
Pulse shape entire signal
Transmit Modulate signal with
1 kHz carrier
Sample for 1 kHz carrier
Record Waveform upon detection of 1 kHz carrier signal
Demodulate signal
Differentially decode
Time synchronize and sample
Frame Synchronize using Barker
Convolutional decodeAssess Bit Error
Technical Standard Activity
Technical standard Provide design guide and inter-operability Encourage competition
Approaches for drafting standards: Only design objective is assigned Students are free to choose techniques Perform regular discussion to define common
parameters Each group draft a standard, among which
the most competitive one is recommended
Conclusions
Project that stimulates students’ interest Use practical design projects which involve
both software and hardware Use tools which are under students’ control Introduce competitions Make it challenging by leaving questions open Draft standards instead of writing ordinary
reports